Consulta: creatorFacets:"SCHAMS, Dieter"
Registros recuperados: 6
Data/hora: 10/06/2024 14:02:49

Expression of mRNA for the Angiopoietin-Tie System in Granulosa Cells during Follicular Development in Cows
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: HAYASHI, Ken-Go; BERISHA, Bajram; MATSUI, Motozumi; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 宮本, 明夫.
Recent findings indicate that the changing profile of angiopoietins (ANPT) and their receptor Tie2 are closely associated with development and regression of the vascular network in the cyclic ovary. We previously reported that mRNA expression for the ANPT-Tie system in theca interna changes during bovine follicular development and atresia, and both ANPTs affect steroidogenesis in the preovulatory follicle. The aim of this study was to investigate mRNA expression for ANPT1, ANPT-2 and Tie2 in granulosa cells (GC) during follicular development in the cow. Bovine follicles were classified according to the estradiol-17β (E2) concentration in follicular fluid (FF) as follows: (1) E2&lt;0.5, (2) 0.5&lt;E2&lt;5, (3) 5&lt;E2&lt;20, (4) 20&lt;E2&lt;180 and (5)...
Palavras-chave: Follicular development; Angiopoietin-Tie system; Granulosa cell; Cow.
Ano: 2004
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2975

Changes in Plasma Metabolic Hormone Concentrations During the Ovarian Cycles of Japanese Black and Holstein Cattle
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: KAWASHIMA, Chiho; KIDA, Katsuya; HAYASHI, Ken-Go; AMAYA MONTOYA, Carlos; KANEKO, Etsushi; MATSUNAGA, Nobuyoshi; SHIMIZU, Takashi; MATSUI, Motozumi; MIYAKE, Yoh-Ichi; SCHAMS, Dieter; MIYAMOTO, Akio; 川島, 千帆; 木田, 克弥; 清水, 隆; 松井, 基純; 三宅, 陽一; 宮本, 明夫.
The aim of the present study was to investigate the changing profiles of plasma metabolic hormones during the ovarian cycles of beef and dairy cattle. We used 16 non-pregnant, non-lactating Japanese Black beef cattle (6 heifers and 10 cows; parity=2.3 ± 0.8) and 12 multiparous Holstein dairy cows (parity=3.0 ± 0.3). Blood samples for hormonal analysis (growth hormone, GH; insulin-like growth factor-I, IGF-1; insulin; and progesterone, P4) were obtained twice weekly for 40 days before artificial insemination for Japanese Black cattle and from 50 to 100 days postpartum for Holstein cows. Luteal phases were considered normal if the P4 concentrations for at least 3 time points over the course of 7 days remained above 1 ng/ml and at least 2 of the time points...
Palavras-chave: Cattle; Insulin-like growth factor-I; Ovarian cycle; Progesterone.
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2984

Changes in the Messenger RNA Expressions of the Endothelin-1 and Angiotensin Systems in Mature Follicles of the Superovulated Bovine Ovary
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: SHIMIZU, Takashi; BERISHA, Bajram; SCHAMS, Dieter; MIYAMOTO, Akio; 清水, 隆; 宮本, 明夫.
The aim of the present study was to examine the messenger RNA expressions of the endothelin and angiotensin systems during the periovulatory phase in gonadotrophin releasing hormone (GnRH)-treated cows. Ovaries were collected by transvaginal ovariectomy (n=5 cows/group), and the follicles (n=5, one follicle/cow) were classified into the following groups: before GnRH administration (control, before LH surge), 3-5 h after GnRH (during LH surge), 10 h after GnRH; 20 h after GnRH, 25 h after GnRH (peri-ovulation), and early corpus luteum (CL) (Days 2-3). Expression of mRNA was investigated using quantitative real-time PCR. The expression of angiotensin converting enzyme (ACE) mRNA significantly decreased immediately after onset of the LH surge and remained at...
Palavras-chave: Angiotensin; Bovine; Endothelin-1; Gonadotrophin releasing hormone (GnRH); Ovulation.
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2987

In Vivo Evidence that Local Cortisol Production Increases in the Preovulatory Follicle of the Cow
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: ACOSTA, Tomas J.; TETSUKA, Masa; MATSUI, Motozumi; SHIMIZU, Takashi; BERISHA, Bajram; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 清水, 隆; 宮本, 明夫.
The aim of the present in vivo study was to monitor real-time fluctuations of cortisol (Cr) in the wall of preovulatory follicles using a microdialysis system (MDS) implanted in the theca layer as well as changes in ovarian venous plasma (OVP) and jugular venous plasma (JVP). Seven cows were superovulated using FSH and prostaglandin F2α injections. Dialysis capillary membranes were surgically implanted into the theca layer of mature follicles and connected to a microdialysis system. Fractions of the perfusates were collected from Day -1 (Day 0=LH surge) to Day 3. No difference in the concentrations of Cr between JVP and OVP was detected throughout the experiment. Circulating concentrations of Cr ranged from 20 to 35 ng/ml 8 h after surgery in ovulatory and...
Palavras-chave: Bovine; Cortisol; Follicle; Ovary; Ovulation.
Ano: 2005
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2980

Intraluteal Release of Prostaglandin F2α and E2 During Corpora Lutea Development in the Cow
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: KOBAYASHI, Shu-ichi; ACOSTA, Tomas J.; HAYASHI, Kanako; BERISHA, Bajram; OZAWA, Takahiro; OHTANI, Masayuki; SCHAMS, Dieter; MIYAMOTO, Akio; 宮本, 明夫.
It is well known that prostaglandin (PG) F2α and PGE2 are actively produced by bovine early corpus luteum (CL) at higher levels than in the CL of later stages. However, there is no in vivo information about the local secretion of PGs within bovine developing CL so far. Thus, the objective of the present study was to determine in detail the real-time changes in PGF2α and PGE2 secretion within developing CL. A microdialysis system (MDS) was surgically implanted into the newly formed CL of 6 cows on Day 3 after GnRH administration (about 1.5 days after ovulation) to induce superovulation following FSH treatment. Both PGF2α and PGE2 release were high during the first 24 h within developing CL but decreased thereafter. These profiles were well reflected in the...
Palavras-chave: PGF2α; PGE2; Developing CL; Cow; In vivo.
Ano: 2002
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2974

Relative Changes in mRNA Expression of Angiopoietins and Receptors Tie in Bovine Corpus Luteum during Estrous Cycle and Prostaglandin F2α-induced Luteolysis: A Possible Mechanism for the Initiation of Luteal Regression
Provedor de dados: Obihiro University of Agriculture and Veterinary Medicine Academic Repository (OAK)
Autores: TANAKA, Jun; ACOSTA, Tomas J.; BERISHA, Bajram; TETSUKA, Masa; MATSUI, Motozumi; KOBAYASHI, Shuichi; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 宮本, 明夫.
Local angiogenesis and angiolysis in the corpus luteum (CL) relate to the luteal function. Recent studies indicate that angiopoietins (ANPT) and their receptors Tie regulate remodeling of microvasculature. We therefore examined 1) the relative changes in the expression of mRNA for ANPT-1, ANPT-2, Tie1 and Tie2 in bovine CL by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) during the estrous cycle and prostaglandin F2α (PGF2α)-induced luteolysis, and 2) the effect of ANPT-2 on progesterone (P4) release from CL at the late stage of the estrous cycle by an in vitro microdialysis system (MDS). The CLs were classified into 4 stages (early: Day 2-5, n=7, mid: Day 8-12, n=15, late: Day 15-17, n=9, regressing: Day &gt;18, n=19). The...
Palavras-chave: Angiopoietin; Angiolysis; Luteolysis; Corpus luteum; Cow.
Ano: 2004
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2977